1. Field of the Invention
The present invention relates to liquid agent containers. More specifically, the present invention relates to liquid agent containers used to store liquid agents, cosmetics and the like, that can prevent liquid agents in the containers from being contaminated by bacteria, microorganism and the like.
2. Description of the Related Art
Generally, liquid agent containers used to store liquid agents, cosmetics and the like therein do not have their interiors aseptically insulated from outside. Once the container has been opened and used, it has its internal liquid agent constantly in communication with the atmosphere through a nozzle hole. Thus there is a possibility that airborne bacteria may enter the interior of the container through the nozzle hole. Furthermore, if in use the nozzle contacts the user's skin, bacteria, microorganism, and the like that adhere to the user's skin may readily enter the interior of the container through the nozzle hole.
Furthermore, liquid agent containers are implemented generally as containers pressed with hands/fingers to discharge their internal liquid agents and recovering their original forms in geometry when they are liberated from being pressed. When the containers deformed as they are pressed recover their original forms in geometry, the containers aspirate the air therein. When conventional liquid agent containers thus aspirate the air therein, there is a possibility that they may also aspirate airborne bacteria, microorganism and the like therein, and once bacteria, microorganism and the like have entered the liquid agent containers, there is a possibility that the bacteria, microorganism and the like may use as nutrients effective components contained in the liquid agents or a buffering agent, a solubilization agent and the like added to stabilize the liquid agents, and may thus increases in the containers.
A container having a nozzle internally provided with a hydrophilic filter has been proposed to prevent bacteria, microorganism and the like from entering the container after use when a liquid agent remaining in the nozzle flows back into the interior of the container or the container pressed and thus elastically deformed recovers its original form in geometry. The hydrophilic filter, however, has in a general condition a nature allowing liquid to pass therethrough and preventing gas from passing therethrough, and the container after its internal liquid is reduced would remain deformed as it has been pressed.
Accordingly there has been proposed a container provided with a nozzle hole and in addition thereto an air vent hole. Patent Document 1 (Japanese Patent Laying-open No. 2004-166978) proposes a liquid agent container provided with a hydrophilic filter between a nozzle and an interior of a main unit of the container and a hydrophobic filter at an air vent path that introduces air into the interior of the main unit of the container to prevent bacteria, microorganism and the like from entering the container after use when a liquid agent remaining in the nozzle flows back into the interior of the container or the container pressed and thus elastically deformed recovers its original form in geometry.
The liquid agent container described in Patent Document 1, as shown in FIG. 7, has a cap 102 having an inner side provided with a filter attachment member 103 having one surface provided with a hydrophobic filter 105 and the other surface provided with a hydrophilic filter 104. Furthermore, between hydrophobic filter 105 and the interior of the container, a flow rate limiter unit is provided. The flow rate limiter unit is configured of a check valve 141 or an orifice.
According to Patent Document 1, when the liquid agent container has a liquid agent flowing from the nozzle back into the interior of the container, hydrophilic filter 104 prevents bacteria, microorganism and the like from entering. Furthermore, when the container's main unit 101 receives air flowing thereinto, hydrophobic filter 105 prevents bacteria, microorganism and the like from entering. In addition, between hydrophobic filter 105 and the interior of main unit 101 of the container, a flow rate limiter unit implemented as check valve 141 or an orifice is provided. This allows the container to internally maintain negative pressure for a period of time sufficient to recover the liquid agent that remains in the nozzle through the hydrophilic filter into the interior of the container.
Patent Document 1: Japanese Patent Laying-open No. 2004-166978